Improved: duplicate-safe graph node creation
POST /api/v1/collections/{id}/graph/nodes and POST /api/v1/tkgs/{tkgId}/graph/nodes now check for an existing prediction/claim with a substantially overlapping title before creating a new one. If a close match already exists on the platform, that existing FactBlock is reused instead of creating a near-duplicate — and if it’s already a node in the same graph, no duplicate node is created either.The response now includes an optional reused: boolean field so you can tell whether your request created something new or matched an existing FactBlock.